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Single 6 Fr Transradial Guiding Catheter for Retrograde Recanalization of Left Coronary Artery Chronic Total Occlusions:‚Äà A Case Series

Tak-Shun Chung, MD and Pierfrancesco Agostoni, MD, PhD

Tak-Shun Chung, MD and Pierfrancesco Agostoni, MD, PhD

ABSTRACT: The retrograde approach for percutaneous coronary intervention, using multiple arterial accesses for contralateral injection and large guiding catheters (7-8 Fr), has largely improved the success rate of recanalization of chronic total occlusions (CTOs). Radial approach and downsizing in this type of intervention are challenging. Our cases series demonstrates that in selected anatomies it is possible, feasible, and safe to perform single 6 Fr transradial guiding catheter retrograde recanalization of left-sided CTO via ipsilateral epicardial or septal collateral channels.

J INVASIVE CARDIOL 2014;26(7):E87-E90

Key words: chronic total occlusion, retrograde approach, radial approach


Coronary chronic total occlusions (CTOs) are a well-known challenge for interventional cardiologists. The new technique of performing percutaneous coronary intervention (PCI) via retrograde collaterals and developments in materials and technology have largely improved the success rate of CTO recanalization.1 However, in order to pass the retrograde channels, multiple arterial puncture sites are frequently needed. The routine is to perform these procedures using large guiding catheters (7-8 Fr) via the femoral approach bilaterally.2 Radial approach and downsizing in retrograde CTO PCI appears challenging. Our cases series demonstrates that in selected anatomies it is possible, feasible, and safe to perform single 6 Fr transradial guiding catheter retrograde recanalization of left-sided CTO via ipsilateral epicardial or septal collateral channels.

Case Report #1. A 58-year-old woman with a non-ST elevation myocardial infarction after major non-cardiac surgery underwent a coronary angiogram showing a CTO of the dominant left circumflex artery (LCX) in its distal segment, just after a large marginal branch, and a severe lesion of the mid-left anterior descending (LAD) artery. No obvious antegrade stump was identified; meanwhile, significant retrograde septal collaterals were noticed from the LAD (at the level of the lesion) to the distal circumflex (Figure 1A). The heart team decided to offer complete revascularization, in first instance via a percutaneous approach. A direct retrograde approach to tackle the LCX CTO was attempted. A Sion Blue wire (Asahi Intecc) supported by a 150 cm Corsair microcatheter (Asahi Intecc) was passed through the LAD and the septal channels back to the distal LCX. The occlusion was then passed with a Pilot 200 wire (Abbott Vascular) in retrograde direction. The Corsair microcatheter could be advanced up to the guiding catheter and gently entered the guiding catheter itself, making a loop out of it (“self-kissing” Corsair; Figure 1D). Then, a 330 cm RG3 wire (Asahi Intecc) was externalized. The Corsair microcatheter was removed and the procedure was completed via the antegrade route on the RG3 wire. After predilatation, 2 overlapping drug-eluting stents were deployed with good angiographic result (Figure 1G). The 330 cm RG3 guidewire was then safely removed by reintroducing the Corsair microcatheter over it. No complications occurred. The patient then underwent successful PCI of the mid-LAD a few days later.

Case Report #2. A 58-year-old man with history of myocardial infarction presented with angina pectoris and anteroseptal inducible ischemia. His coronary angiogram showed single-vessel disease, with mid-LAD CTO and retrograde epicardial collaterals from a large obtuse marginal (OM) artery. There was a clear proximal stump at the level of the CTO (Figure 1B). Antegrade approach was attempted with a Sion Blue wire and FineCross microcatheter (Terumo Corporation) support. However, after opening the proximal part of the CTO, the Sion Blue wire went into a diagonal artery and the distal part of the CTO was not crossed. The proximal LAD was predilated and we switched to a retrograde approach. The Sion Blue wire was left in the diagonal artery as a proximal marker. A Pilot 200 wire successfully passed via the OM and via the epicardial collaterals to the apical LAD and a 150 cm Corsair microcatheter was advanced through this way. The LAD CTO was successfully passed using a Miracle 12 wire (Asahi Intecc). The Corsair microcatheter was then advanced up to the left main. However, it could not reach the tip of the guiding catheter because it was too short. In any case, it was still possible to externalize a 330 cm RG3 wire. In an attempt to exchange the RG3 wire for a normal antegrade wire, it was not possible to advance a second microcatheter via the antegrade route over the RG3 wire via the 6 Fr guiding catheter, leaving the retrograde Corsair microcatheter in situ (Figure 1E). We finally used 2 FineCross microcatheters inserted from both ends of the RG3 wire, and the microcatheter tips “kissed” at the distal part of the target vessel (Figure 2). It was then possible to remove the RG3 wire via the retrograde collaterals because they were protected by the retrograde FineCross microcatheter. In addition, the antegrade channel was preserved by the antegrade FineCross microcatheter. An Extra-support wire (Boston Scientific) was inserted via the antegrade FineCross microcatheter without difficulty. Then, the LAD was treated after predilatation with 4 overlapping drug-eluting stents. Balloon angioplasty was performed in the direction of the diagonal artery through the stent struts. Final postdilatation of the entire stented segment led to a good angiographic result (Figure 1H). No complications occurred.

Case Report #3. A 59-year-old man with history of myocardial infarction and previous PCI of the left main-ramus intermedius (RI) and known CTO of the mid-LAD presented with out-of-hospital cardiac arrest because of ventricular fibrillation. An implantable cardioverter defibrillator (ICD) was implanted for secondary prevention. Magnetic resonance of his heart, performed just before ICD implantation, showed impaired left ventricular function and a large area of viability in the anteroseptal wall. His coronary angiogram showed a patent stent in the left main-RI and the known mid-LAD CTO with retrograde epicardial collaterals from the RI. The proximal entry stump of the LAD CTO was uncertain because a septal branch was present at this level (Figure 1C). After wiring the septal with a Sion Blue wire, direct retrograde approach was chosen. A Sion Blue wire with 150 cm Corsair microcatheter support was easily navigated to the distal LAD via the retrograde collaterals. A Miracle 6 (Asahi Intecc) was used to perforate the distal cap of the CTO and it successfully passed the CTO lesion. The Corsair was then advanced from the distal LAD up to the guiding catheter (“self-kissing” Corsair; Figure 1F). Then, a 330 cm RG3 wire was externalized. Because the LAD appeared severely calcified, the procedure was continued with the RG3 wire in situ in order to improve guidewire support. The Corsair microcatheter was removed. The LAD was predilated with normal and non-compliant balloons and 2 drug-eluting stents were deployed from the ostium of the LAD (T-stenting technique with the old left main-RI stent) up to the mid-segment. Final kissing balloon was performed in the left main-LAD-RI with 2 balloons over the antegrade and retrograde part of the same RG3 wire (Figure 3). Finally, the Corsair microcatheter was reinserted via the retrograde route and the RG3 wire was removed. The final angiogram showed a good result and no damage of the collaterals (Figure 1I). No complications occurred.

Discussion. The most common cause of procedural failure in CTO PCI is the inability to cross the CTO lesion with the wire. The retrograde approach has definitely improved the chance to succeed in passing the CTO lesion. Most retrograde CTOs are performed with multiple arterial access sites and multiple and large-sized guiding catheters.2 The bifemoral approach is commonly used, also due to the perception of reduced guiding catheter support from the radial approach. A number of publications have demonstrated the feasibility of radial approach for CTO PCI.3 Moreover, there is a small number of CTOs with ipsilateral retrograde collateral. In these selected anatomies, the procedure may be simplified using a single catheter for both antegrade and retrograde approach. There has been one publication showing the feasibility of single 7 Fr guiding catheter radial approach for LAD CTO by ipsilateral septal collateral circulation.4 Our case series supports the concept of using a single guiding catheter for radial approach for selected CTO lesions and selected ipsilateral collaterals. Moreover, we demonstrate the feasibility of using a single 6 Fr guiding catheter for CTO lesions of both the LAD and LCX. However, the 6 Fr guiding catheter, due to its small caliber, cannot accommodate all the needed tools after placement of the Corsair microcatheter. The Corsair microcatheter needs to be removed to give space to other devices needed to complete the procedure successfully. One solution is to complete the procedure with a single RG3 wire (with both ends externalized from the same guiding catheter), and this also gives very good support. A microcatheter should be reinserted via the retrograde channel after completion of the procedure for protection of the retrograde vessel during removal of the RG3 wire. On the other hand, exchange of the externalized RG3 wire with a normal antegrade wire to complete the procedure is also possible. In this case, we have demonstrated the use of 2 FineCross microcatheters (1 antegrade and 1 retrograde) to protect the retrograde vessel and to exchange the RG3 into an antegrade coronary wire.

Although we demonstrated that the above techniques are technically feasible, their potential disadvantages and limitations should be kept in mind. First, these techniques are only applicable to LAD or LCX CTOs with ipsilateral collaterals. Second, in some circumstances, the removal of the retrograde Corsair microcatheter may create the risk for collateral vessel injury from the “naked” guidewire. Third, in case of complications (such as dissection of the donor vessel), treatment would be very challenging through a single 6 Fr guide catheter. In this case, the switch to double arterial access should be promptly considered by inserting a second guiding catheter via the contralateral radial or the femoral artery. This guiding catheter can be used in a “ping-pong” fashion with the guiding catheter already located in the coronary artery to track additional hardware in order to solve the complication.

Conclusion. In selected CTO anatomies, a retrograde recanalization procedure can be performed with a single 6 Fr guiding catheter through the radial approach.


  1. Galassi AR, Tomasello SD, Reifart N, et al. In-hospital outcomes of percutaneous coronary intervention in patients with chronic total occlusion: insights from the ERCTO (European Registry of Chronic Total Occlusion) registry. EuroIntervention. 2011;7(4):472-479.
  2. Syrseloudis D, Secco GG, Barrero EA, et al. Increase in J-CTO lesion complexity score explains the disparity between recanalisation success and evolution of chronic total occlusion strategies: insights from a single-centre 10-year experience. Heart. 2013;99(7):474-479.
  3. Rinfret S, Joyal D, Nguyen CM, et al. Retrograde recanalization of chronic total occlusions from the transradial approach; early Canadian experience. Catheter Cardiovasc Interv. 2011;78(3):366-374.
  4. Egred M. Transradial retrograde recanalization of totally occluded left anterior descending artery using a single 7 Fr guiding catheter. J Invasive Cardiol. 2013;25(1):57-60.


From the Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.

Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. The authors report no conflicts of interest regarding the content herein.

Manuscript submitted November 19, 2013, provisional acceptance given December 16, 2013, final version accepted February 3, 2014.

Address for correspondence: Pierfrancesco Agostoni, MD, PhD, Department of Cardiology, University Medical Center Utrecht, Heidelberglaan 100, E.04.201, 3584 CX, Utrecht, the Netherlands. Email: